Tap.



` PATENTED JULY 5, 1904.

. H. E. Am.

APPLIOATION FILED Nov. 12.1903.

No. 764,409, PATENTED JULY-5, 1904.

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N 0 M 0 D E L 3 S H E E T B S H E E T 2.

PATBNTBD JULY 5, 1904. H. E. ADT.

TAP.

APPLIOATION FILED Nov.12,1eoa.

3 SHEETS-SHEET. 8.

N0 MODEL.

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INVENTOR YYTNESSES ATTORNEYS UNITED STATES i Patented July 5, 1904.

PATENT OFFICE.

HOI/VARD E. ADT, OF NEW HAVEN, CONNEO'IIGUT, ASSIG-NOR TO GEO- METRIC DRILL COMPANY, OF' WIESTVILLE,

PORATION OF DELAWARE.

CONNECIIOUT, A COR- TAP.

SPECIFICATION forming part of Letters Patent N0. 764,409, dated uly 5, 1904.

Application filed November 12, 1903. Serial No.180,922. (No model.)

To (all whom, t concern:

Be it known that I, HOWARD E. ADT, a citi- Zen of the United States of America, residing in the city of New Haven, county of New Haven, State of Connecticut, have invented certain new and useful Improvements in Taps,

' of which the following is a specification.

My invention relates to certain improvements in the construction of screw-cutting taps, the main objects of my invention being to permit and facilitate the grinding and setting up of the cutters to make up forwear, to

facilitate their insertion in place, and to improve the means for securing and. adjusting the cutters.

While my improvements are applicable toV different forms of screw-cutting taps, I have shown them lin the accompanying drawings as applied to the construction oftaps illustrated in the Patent of W. J. Smith, No.

y 625,611, dated May 23, 1899.

Figure l is a side view of the tap. Fig. 2 is an end view of the cutter end of the tap. Fig. 3 is a longitudinal section on the line 3 3, Figs. l and 2. Fig. I is an enlarged transverse section on the line 4L A, Fig. 8. Fig. 5

` is an inner faceview of the locking-plate ldetached. Fig. 6 is a view of the actuating'- collar on the line 6 6, Fig. 3, and a section through the stock and cam-bar, where the cam-bar is connected to the collar by a pin. Fig. 7 is a view of the other face of the collar in a section taken on the line 7 7, Fig. 3. Fig. 8 is a longitudinal sectional view of the cutter end of the tap, and Figs. 9, 10, and 11 are detached views of adjusting' and securing collars for the cutters.

l and then put them back in the stock. ring R is then adjusted forward over the rear springs S, mounted in the stock, Fig. 8. The free ends of these springs enter holes (Z in the cutters. 'Io facilitate the introduction of the cutters D into place, Fig. 8, the extreme forward ends of the springs are turned outward, and the mouth of the opening (Z at the rear end of each cutter is flared toward the back of the cutter, as at (Z, Fig. 8. The cutters are confined longitudinally between an adjustable ring R on the stock and the plate K, which is secured at the forward outer end of the stock by screws Figs. 2 and 3. I make this ring R adjustable longitudinallyon the stock, onto which it is set from the forward end of the tap, and I provide means for securing the ring firmly in its adjusted position. When the forward teeth ofthe tap become too much worn to do their` work efficiently, the teeth behind them, which have less work to do, are but little worn. It is customary to put in new cutters when the front teeth of the old cutters are worn away. I take out the cutters when i the forward. teeth are worn away and I grind,

down the forward ends of the cutters equally The ends of the cutter-slots toward the forward end of the tapto grip the cutters between it and the plate K. I then secure the ring R in place, preferably by means of `a ring R', Figs. l and 3, which is threaded onto a threaded part of the stock behind the ring R. I prefer to form this ring R with inwardly-projecting tongues fr, Figs. 8, 9, and 10, to project into the radial slots which receive the cutters D.

Instead of having' a ring R' to act as a set* nut for the ringR the latter may be provided with radial securing-screws i", as show-n in Fig. 10, these screws, when the ring has been adjusted toits required position, being turned to engage with the stock to so hold the ring.

In the modification shown in Fig. 11 the ring R2 is shown as threaded internally to engage with the same threaded part of the stock onto which the ring R is screwed. In this case the tongues fr are omitted.

As in the construction illustrated in Patent No. `625,611 there is secured to the stock, as by radial screws, a face-plate F, and back of this plate is the spring-actuated collar C, by means of which the cam bar B is rocked through the medium of a radial pin E, Figs. 3, 6, and 7, litted into a transverse opening in the cam-bar and passing freely through a slot fr, Fig. 6, in the stock. The outer end of this pin E tits in a keyway e in the inner face of the operating-ring C. rI he collar C is provided with a handle Cl, by which it may be manipulated. In the forwardface of this ring C is an annular groove to receive a spiral spring H, o'ne end of which bears against a pin L, Figs. 3 and 7, on the collar C, while the other end bears against apin f, Fig. 7, which is carried by the back of the face-plate F and projects into the groove in the collar C containing the spring' H. This spring tends constantly to turn the collar C in the direction of the arrow, Fig. 7, pressing the pin E against the end of the slot Fig. 6, when the operating-collar C is freed from the locking-plate G. This locking-plate G is connected to the stock by a key or feather y, so that while the plate cannot turn upon the stock it can slide longitudinally thereon to a sufficient extent to engage its pin g with or disengage it from a notch c in the rear face of the collar C, Fig. 6. In Fig. 3 the plate G is shown moved back to disengage the pin g from the collar C. The plato G has radial pins 15 projecting through late ral openings a into the hollow interior of the stock, Figs. 3 and 4, and bearing against a shoulder on the piston 16, which is pressed toward the cutter end of the stock by a spring 17. By this means `the stop-plate G is constantly pressed up toward the operating-ring C, and when the latter has been turned to such position as will cause the cam-bar B to project the cutters the spring 17 will press the plate G forward to' throw the pin g into engagement with the notch c of the collar C, Fig. 6.

In order to increase the accuracy of adjustment of the locking-pin g, and so increase the accuracy of the degree of projection of the cutters when the cutter-carrying part and the cam are thereby locked together, I mount the pin g upon a ring G', which is iitted (and preferabl y threaded) onto a reduced part 20 of the plate G, as shown in Fig. 3. I also provide at the back of the ring G an abutment g',

- projecting into a slot 18, Figs. 3 and 4, in the plate G. I thread into the plate G screwstops 19 to bear on opposite sides of the abutment 18, Fig. 4. By adjusting these screwstops the ring G', carrying the locking-pin g, can be adjusted rotarily with great nicety to change the locking-point of the collar C, and consequently the rotary position of the cambar B, with relation to the cutters, and therefore the degree of projection of the cutters when in cutting position. B-y adjusting both screws to bear against the opposite faces of the abutment the adjusting-ring Gl will be securely locked in vits adjusted position. As shown in Fig. 1, I prefer to provide graduations on the plate and ring to show degree of adjustment.

To push the locking-plate G backward to disengage the pin g from the collar C, I prefer to secure to the outside of the plate G longitudinally-slotted bars 21, similar to the t bar 6a of Patent No. 625,611; but the bars 21 have secured to their forward ends a ring 22, surrounding the cutter end of the tap and adapted to come into contact with the work or the frame carrying the work, and so push back the locking-plate G against the spring 17 to disengage the cutters from the work.

I claim as my invention- 1. A tap provided with a slotted stock and cutters therein, means for setting the cutters in and out radially, an end plate against which the forward ends of the cutters bear, a ring bearing against the back ends of the cutters and adjustable over the cutter-slots toward the forward end of the tap to set the cutters forward when ground at the ends and means for securing the ring in its adjusted position.

2. The combination of a stock and cutters with a rotary cam-piece to actuate the cutters, and a locking-plate for the cam-piece, the locking-plate having a ring threaded into it, and carrying the locking means.

3. The combination of stock and cutters* with a rotary cam-piece to actuate the cutters and a locking-plate for the cam-piece, the locking-plate having a ring carrying the locking means and an abutment, with screws in the plate to bear against opposite faces of the abutment to adjust the ring rotarily and to lock it.

4. The combination of the stock and cutters with a rotary cam to actuate the cutters, a collar to actuate the cam and a longitudinally- IOO movable locking-plate to engage thercollar,

the locking-plate having a rlng carrying locking means, and an abutment and screws in the plate to bear against opposite faces of the abutment to adjust the ring rotarily and to lock it.

5. The combination of the stock and cutters with a rotary cam to move the cutters to cutting position, and means to lock the cuttercarrying part and the cam together when the cutters are in -cutting position, said locking means including a rotarily-ad j ustable ring and a plate mounted on the stock, one of these parts having an abutment and the other having adjusting-screws to bear on opposite sides of the said abutment, all substantially as described.

IIO

6. A tap provided with a slotted stock and In testimony whoreoflhavo signed my name cutters in the slots, an end plate against which to this specification in the presence of two "subthe forward ends of tho cutters bear, a 1onscribing witnesses.

gitudinally-adjustable ring having tongues HOWARD E. ADT. 5 projecting into tho cutter-slots andbearing VVitnosses:

against the back ends of the cutters and means W. J. SMITH,

for securing' the ringl in its adjusted position. L. W. BEEoI-IER. 

